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In this study, we designed and synthesized two blue fluorescence materials using 7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7H-benzo[b]fluoreno[3,4-d]thiophene substituted anthracene derivatives. To characterize their electroluminescent properties, we fabricated the OLED devices using these two emitting materials. Particularly, a device using 7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7Hbenzo[ b]fluoreno[3,4-d]thiophene showed maximum values of luminous efficiency, power efficiency, and external quantum efficiency of 2.42 cd/A, 1.48 lm/W, 3.08% at 20 mA/cm2, respectively with CIE ( x, y ) coordinates of (0.15, 0.09) at 8.0 V.

Self-assembled nano-layering resulting from combined ionic and hydrogen-bonding interactions of phosphate functional monomers with zirconia have been proposed. The purpose of this study was to investigate the bond strengths of two phosphate monomer-containing adhesive resin cements (Panavia F 2.0 and RelyX U200) to a conventional tetragonal zirconia (Lava Plus, LP) and a new cubic zirconia (Lava Esthetic, LE), with three different shade zones, after air-abrasion. The structures of the zirconia surfaces were examined with scanning electron microscopy (SEM) and X-ray diffractometry (XRD). Vickers hardness and fracture toughness of the surfaces were also evaluated using a hardness tester. After air-abrasion (with 50 µ m Al₂O₃ at a pressure of 0.25 MPa), the surface roughness was measured using confocal laser scanning microscopy (CLSM) and the resin cements were bonded (diameter: 2.38 mm) to the surfaces. All bonded specimens were stored in water at 37 °C for 24 h before performing the shear bond strength (SBS) test ( n = 15). In the SEM images, the LP group showed a finer grain size than the LE groups. The XRD patterns confirmed that LP and LE had tetragonal and cubic phases, respectively. Although there were no significant differences in Vickers hardness among the four groups ( p = 0.117), the three LE groups revealed inferior fracture toughness to the LP group ( p < 0.001). However, neither the surface roughness of the air-abraded zirconia surfaces nor SBS values of each resin cement bonded to them were significantly different ( p > 0.05). In conclusion, no significant difference in SBS value was detected between the tetragonal and cubic zirconia within each resin cement used, probably due to the similar surface roughness of the air-abraded zirconia ceramics.

Highly efficient blue fluorescent 7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7H-benzo[6,7]indeno[1,2- f]quinoline derivatives, based on benzo-indeno-quinoline and phenylanthracene were designed and synthesized. To test their electroluminescent properties, organic light-emitting diodes (OLEDs) were fabricated with the configuration of indium-tin-oxide (ITO) (150 nm)/4,4',4″-Tris[2- naphthyl(phenyl)amino]triphenylamine (2-TNATA) (30 nm)/N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'- biphenyl)4,4'-diamine (NPB) (20 nm)/blue emitting materials (20 nm)/bathophenanthroline (Bphen) (30 nm)/Liq (2 nm)/Al (100 nm). The devices using these blue materials as emitters showed efficient blue emission. Particularly, a device employing 7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7Hbenzo[ 6,7]indeno[1,2-f]quinoline as an emitting layer yielded the best performance with a luminous efficiency (LE), power efficiency (PE), and external quantum efficiency (EQE) and the Commission International de L'Eclairge (CIE) coordinates of 4.60 cd/A, 3.07 lm/W, 4.32% at 20 mA/cm², and (0.16, 0.12) at 8.0 V, respectively.

Self-assembled nano-layering resulting from interaction of the phosphate functional group of adhesive monomers with zirconia ceramic surface has been proposed. The purpose of this study was to investigate the bond strengths of two adhesive resin cements (Panavia F 2.0 and BisCem) containing phosphate monomers added with various concentrations (0.0, 1.0, 3.0, and 5.0 wt%) of triethylene glycol dimethacrylate (TEGDMA) to air-abraded zirconia ceramic. The polished/air-abraded zirconia plates (KaVo Everest® ZS-Ronde) were imaged using atomic force microscopy and the average surface roughness (R a ) values were calculated (n = 5). The surface energy parameters of the zirconia plates and the resin cements were calculated based on the extended Fowkes theory. All resin-bonded (diameter: 2.38 mm) zirconia specimens were stored in water at 37 °C for 24 h and then half of them additionally thermocycled 10,000 times before the shear bond strength (SBS) test (n = 10). Air-abrasion of zirconia surface significantly increased the γ h S (hydrogen bonding component) value ( p < 0.001), as well as greatly increasing the surface area ( p < 0.001). For both resin cements, the γ h S (dipole-dipole component) gradually increased with increasing incorporated TEGDMA concentrations, whereas the γ h S gradually decreased. Overall, the addition of 3.0 wt% of TEGDMA consistently resulted in higher SBS values even after thermocycling. Under the tested condition, reducing the concentration of the adhesive monomers with phosphate functional group by adding the dimethacrylate monomer (up to 3.0 wt%) increased the bond strength between the resin cements and zirconia ceramic.

Ice accumulation on the surface of railway electrical wires can cause significant problems in the winter season. Different anti-icing liquids have been used to prevent the formation of ice on different surface substrates. The most common anti-icing liquids are ethylene glycol mixtures. Recently, propylene glycol, due to its lesser toxicity, has been considered as an alternative anti-icing agent. However, propylene glycol mixtures have some limitations, in that their degradation can lead to corrosion of the metal substrate. As detailed in the literature, (3-aminopropyl)-triethoxysilane (APTES), the precursor of magnesium aminoclay (MgAC), has been used to protect metal substrates from corrosion. In the present study we examined the potential of MgAC as an APTES-alternative additive in propylene glycol mixtures. The results showed that the anti-icing properties of the propylene glycol mixtures were maintained in the presence of MgAC (at 0.1, 0.5, and 1.0 wt.% concentrations). Furthermore, MgAC's potential as a thickening agent was shown in the increased viscosity of the propylene glycol/MgAC mixtures relative to the propylene glycol mixtures. The addition of MgAC also rendered the propylene glycol mixtures more hydrophilic. However, MgAC addition also led to corrosion due to the excess amounts of amine groups in the anti-icing solution. In this paper, the corrosion mechanism of MgAC is explained in the paper. In the future, the anti-icing and anticorrosion properties of propylene glycol/MgAC mixtures at low concentrations (<0.1 wt.%) should be more fully investigated.

Here, red phosphorescent platinum(II) complexes based on tetradentate pyridine-containing lig-ands are studied. To investigate their electroluminescent properties, multilayer devices were fabricated in the following sequence; ITO (180 nm)/4,4',4″-Tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA) (30 nm)/ N , N '-di(1-naphthyl)- N , N '-diphenyl-1,1'-biphenyl)4,4'-diamine (NPB) (20 nm)/ Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) (10 nm)/4,4'-Bis( N -carbazolyl)-1,1'-biphenyl (CBP) (20 nm)/Platinum(II) complex (20 nm)/1,3,5-Tris(1-Phenyl-1H-benzimidazol-2-yl)benzene) (TPBi) (40 nm)/Liq (2 nm)/Al (100 nm). In particularly, a device using platinum(II) complex based on N -(3,5-di-tert-butylphenyl)-3-(pyridin-2-yl)- N -(3-(pyridin-2-yl)phenyl)benzenamineligand showed the efficient red emission, with a luminous efficiency, power efficiency, and external quantum efficiency of, and the Commission International de LEclairge (CIE) coordinates of 27.26 cd/A, 10.54 lm/W, 8.50% at 20 mA/cm², and (0.65, 0.33) at 11.0 V, respectively.

In this study, we synthesized and characterized two novel deep blue emitting materials based on indenoquinoline-substituted phenylanthracene derivatives. Multilayer organic light-emitting diodes were fabricated with the following sequence: indium-tin-oxide (ITO)/4,4',4″-tris[2-naphthyl(phenyl)amino (2-TNATA)/4,4'-bis( N - N -naphthyl)- N -phenylamino) biphenyl (NPB)/Blue emitting material ( 1 or 2 )/Bathophenanthroline (Bphen)/lithium quinolate (Liq)/Al. A device B using '7,7-dimethyl-9-(10-phenylanthracen-9-yl)-7H-indeno[1,2-f] isoquinoline ( 2 )' as an emitter showed the efficient emission with the luminous efficiency, power efficiency, and external quantum efficiency of 2.30 cd/A, 1.02 lm/W, 2.94% at 20 mA/cm², respectively. This device exhibited deep-blue emission with the Commission Internationale De LÉnclairage (CIE) coordinates of (0.16, 0.08) and λ max = 436 nm at 8.0 V.

In this study, we designed and synthesized two phosphorescent emitting materials based on tetradentate pyridine-containing ligands. Their photophysical properties were examined for OLEDs and multilayer devices using these materials were fabricated in the following sequence; ITO (180 nm)/4,4',4″-Tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA) (30 nm)/ N , N '-di(1-naphthyl)- N , N '-diphenyl-1,1'-biphenyl)4,4'-diamine (NPB) (20 nm)/Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) (10 nm)/4,4'-Bis( N -carbazolyl)-1,1'-biphenyl(CBP): 5, 8, 15% Platinum (II) complexes (20 nm)/1,3,5-Tris(1-Phenyl-1 H -benzimidazol-2-yl)benzene) (TPBi) (40 nm)/Liq (2 nm)/Al (100 nm). In particularly, a device using Platinum (II) complex based on A/-(3,5-di-tert-butylphenyl)-6-phenyl- N -(6-phenylpyridin-2-yl)pyridin-2-amine ligand showed the efficient emission, with luminous efficiency, power efficiency, and external quantum efficiency, and the Commission International de LEclairge (CIE) coordinates of 29.29 cd/A, 9.37 lm/W, 8.66% at 20 mA/cm2, and (0.32, 0.62) at 8.0 V, respectively.

The adhesion property of zirconia powder-incorporated primers was investigated in vitro with the aim of enhancing the resin bond strength to zirconia ceramic. A commercial zirconia primer was modified through the addition of 0 (control), 5, 10, 25, and 50 wt% of a zirconia powder (codes: ZP0, ZP5, ZP10, ZP25, and ZP50, respectively). Prior to primer modification, the powder was characterized via differential scanning calorimetry (DSC) and Fourier-transform infrared (FTIR) spectrophotometry. The surfaces of dental zirconia ceramic discs were air-abraded and treated with one of the five primers. One resin composite cylinder (diameter: 2.38 mm) was bonded on one specimen surface ( n = 12/group). The bonded specimens were all stored for 24 h in distilled water at 37 °C and subjected to 5000 thermal cycles prior to shear bond strength (SBS) testing. The DSC and FTIR analyses confirmed that the zirconia powder contained an organic binder. The SBS test results showed that the groups could be arranged as follows, ZP25 > ZP10 > ZP5 > ZP0, i.e., in descending order of the mean value. The lowest SBS value was obtained for the ZP50 group. The results suggest that the incorporation of a zirconia powder into a primer represents a promising modification method for improving the resin bond strength to zirconia ceramic.

In this study, we designed and synthesized two blue fluorescence materials using phenylanthracenesubstituted-indenoquinoline derivatives by Suzuki coupling reaction for organic light-emitting diodes (OLEDs). In order to study their electroluminescent properties, we fabricated the OLED devices using these two materials as emissive layer (EML) with the following sequence: indium-tin-oxide (ITO, 180 nm)/4,4',4″-tris[2-naphthyl(phenyl)-amino]triphenylamine (2-TNATA, 30 nm)/ N,N '-diphenyl- N,N '-(2-napthyl)-(1,1'-phenyl)-4,4'-diamine (NPB, 20 nm)/Blue emitting materials (20 nm)/4,7-Diphenyl-1,10-phenanthroline (Bphen, 30 nm)/lithium quinolate (Liq, 2 nm)/Al (100 nm). In particular, a device using 11,11-dimethyl-3-(10-phenylanthracen-9-yl)-11 H -Indeno[1,2- b ]quinoline in emitting layer showed luminous efficiency, power efficiency, and external quantum efficiency of 2.18 cd/A, 1.10 lm/W, 2.20% at 20 mA/cm², respectively, with Commission Internationale d'Énclairage (CIE) coordinates of (0.15, 0.11) at 8.0 V.

In this study, we designed and synthesized blue emitting materials based on 1, 10-phenanthroline derivatives. OLED devices using these materials were fabricated in the following sequence; indium-tin-oxide (ITO) (180 nm)/ N , N '-diphenyl- N , N '-(2-napthyl)-(1,1'-phenyl)-4,4'-diamine (NPB) (50 nm)/Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) (10 nm)/Blue materials (20 nm)/2,2',2″-(1,3, 5-Benzinetriyl)-tris(1-phenyl-1- H -benzimidazole) (TPBi) (30 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). Particularly, a device using 2-(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-1-phenyl-1Himidazo[ 4,5-f][1,10] phenanthroline as a blue emitter showed the maximum values of luminous efficiency, power efficiency, and external quantum efficiency of 1.45 cd/A, 1.52 lm/W, 0.99%, respectively with the Commission Internationale d'Énclairage (CIE) ( x,y ) coordinates of (0.16, 0.14) at 8.0 V.

Phosphorescent Pt(II) complexes based on phenylbenzoazole ligands were synthesized and their photophysical properties were investigated for OLEDs. Multilayered OLEDs devices using these complexes as emitters showed the efficient emissions, which are very sensitive to the structural and photophysical properties of Pt(II) complexes. In particularly, a device C using Pt(II) complex 2 based on phenylbenzoazole ligand as the dopant exhibited efficient emission with a luminous efficiency, a power efficiency, an external quantum efficiency, and CIE coordinates of 8.03 cd/A, 2.79 lm/W, 4.84% at 20 mA/cm², and (0.63, 0.35) at 10.0 V, respectively.

To develop the efficient emitters for organic light-emitting diode (OLED), three indeno-type polyaromatic hydrocarbons materials were designed and synthesized through Buchwald-Hartwig amination. OLED devices using these materials were fabricated in the following sequence: indium-tin-oxide (ITO) (180 nm)/ N,N '-diphenyl- N,N '-(2-napthyl)-(1,1'-phenyl)-4,4'-diamine (NPB) (50 nm)/Emitting materials ( 1-3 ) (30 nm)/4,7-diphenyl-1,10-phenanthroline (BPhen) (30 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). All devices showed the efficient emissions. In particular, a device using 8,8-dimethyl- N,N -diphenyl-8 H -indeno[2,1- b ]fluoranthen-6-amine ( 2 ) as efficient emitter showed luminous efficiency, power efficiency, and external quantum efficiency of 8.35 cd/A, 5.70 lm/W, 2.37% at 20 mA/cm², respectively, with Commission Internationale d'Énclairage (CIE) coordinates of (0.37, 0.59) at 6.0 V.

In this study, the morphological effects of ZnO on the antimicrobial and deodorant activities of synthetic fibers were investigated. Three different polyethylene terephthalate (PET)/ZnO filaments were prepared by incorporating various ZnO nanostructures (rods, plates, and spheres) into PET filaments via a melt-spinning process. The antimicrobial activity of the as-prepared fibers was evaluated by the shake-flask method using two types of bacteria ( Staphylococcus aureus and Klebsiella pneumoniae ). The deodorant activity of the as-prepared fibers was evaluated by the gas detection tube method. All the PET/ZnO filaments exhibited excellent antimicrobial activity with a bacterial reduction value of 99.9%. The PET/ZnO rod filament showed the best deodorant performance of 60.0%. Both the antimicrobial and deodorant activities of the PET/ZnO filaments were influenced by the morphology of ZnO. However, the morphology of ZnO had a different effect on each functionality of the PET/ZnO filaments. The antimicrobial activity of the PET/ZnO filaments was mainly affected by the physical properties of ZnO rather than its morphology. By contrast, the deodorant activity of the PET/ZnO filaments was highly influenced by the morphology of ZnO.

Novel blue thermally activated delayed fluorescence (TADF) emitters, D1-DPS and D2-DPS , were designed and synthesized. Diphenyl sulfone (DPS) group functioned as a common acceptor, and it combined with each of two different spiro-acridine groups, D1 and D2. The calculated energy differences (Δ E ST ) of the singlet and triplet excited states of D1-DPS (0.062 eV) and D2-DPS (0.128 eV) had sufficiently small Δ E ST values, which is favorable in the thermally activated reverse intersystem crossing (RISC) process from the T 1 state to the S 1 state. A device doped 10 wt% of D2-DPS with ADN host material, obtained 5.05% of external quantum efficiency with deep-blue emission having CIE xy coordinates of (0.152, 0.065). The results showed that these molecules are promising host-free TADF deep-blue emitters by inhibiting concentration quenching.

Two fluorescent benzo[g]quinoline derivatives were synthesized via Friedländer synthesis. Multilayered OLEDs using benzo[g]quinoline derivatives as the emitters showed unexpected emissions by electroplexes. Particularly, a device using 2-(naphthalen-3-yl)-4-phenylbenzo[g]quinoline as an emitting material exhibited efficient emission with a luminous efficiency, a power efficiency, an external quantum efficiency, and CIE coordinates of 3.58 cd/A, 1.11 lm/W, 1.08% at 20 mA/cm², and (0.36, 0.56) at 1,000 cd/m², respectively.

In this study, we designed and synthesized three fluorescent blue emitting materials based on indenophenanthrene derivatives. These derivatives were synthesized by Suzuki coupling reaction. Particularly, a device C using 9,10-bis(9,9-dimethyl-9H-indeno[2,1-l]phenanthren-11-yl)anthracene as blue emitter showed maximum values of luminous efficiency, power efficiency, and external quantum efficiency of 7.58 cd/A, 5.87 lm/W, 4.20%, respectively.

This study investigated the room-temperature compressive property and deformation behavior of microporous STS 316L stainless steel tube for catalyst manufactured with powder sintering after two-way compression molding. The microporous tube was manufactured using STS 316L powder stocks with an outer diameter of 30 mm, inner diameter of 25 mm and length of 120 mm. In initial microstructure observed from different directions and locations, the porosity was measured as 32%, and the relative density obtained using micro-computed tomography was 0.54. Phase analysis did not identify phases other than γ -Fe. In a room temperature compression test, compressive yield strength measured 32 MPa. Observation of fractpgraphy after compression test revealed that dimples were formed at the powder-powder interface during the process where necks were disconnected. Based on the above findings, this study attempted to identify the deformation behavior of microporous STS 316L material manufactured with powder sintering after two-way compression molding and powder sintering process.

Among the three primary colors, blue-emitting materials are limited by the wide energy band gap. In this study, we designed and synthesized emitting materials based on indeno-phenanthrene/ triphenylene derivatives. Organic light emitting-diodes (OLEDs) using these materials were fabricated in the following sequence; ITO/ N , N '-diphenyl- N , N '-(2-napthyl)-(1,1'-phenyl)-4,4'-diamine (NPB) (500 Å)/Blue materials (30 nm)/4,7-diphenyl-1,10-phenanthroline (BPhen) (30 nm)/lithium quinolate (Liq) (20 Å)/Al (1000 Å). All the devices showed efficient blue emission. Particularly, a device using 10,10-dimethyl- N , N -diphenyl-10 H -indeno[1,2- b ]triphenylen-12-amine as an emitter exhibited luminous efficiency, power efficiency, and external quantum efficiency of 3.62 cd/A, 1.83 lm/W, 2.82% at 20 mA/cm², respectively, with Commission Internationale d'Énclairage (CIE) coordinates of (0.16, 0.15) at 6.0 V.

Herein, we designed and synthesized emitting materials based on naphthoanthracene with the different arylamino-substituents. Organic Light Emitting-Diodes (OLEDs) devices using these materials were fabricated in the following sequence; ITO/ N , N '-diphenyl- N , N '-(2-napthyl)-(1,1'-phenyl)-4,4'- diamine (NPB) (500 Å)/Emitters (400 Å)/Alumium quinolate (Alq₃) (150 Å)/lithium quinolate (Liq) (20 Å)/Al (1000 Å). All devices showed efficient emissions. In particular, a device using 4-((5,5-dimethyl-9-phenyl-5H-naphtho[3,2,1-de]anthracen-3-yl)(phenyl)amino)benzonitrile as an emitter exhibited the luminous efficiency, power efficiency, and external quantum efficiency of 9.15 cd/A, 6.36 lm/W, 2.72% at 20 mA/cm², respectively, with the Commission Internationale d'Énclairage (CIE) coordinates of (0.30, 0.62) at 6.0 V.

Icing of railway contact wires in the cold climates of the USA, Canada, China, Japan, and South Korea can cause significant problems and delays in the operation schedules of electric-powered trains and subway cars. As anti-icing methods, manual de-icing, contact-wire thermal running, resistive-wire-heating de-icing, and chemical de-icing have all been explored and tested. Among them, environmentally friendly chemical de-icing based on the same concept as that of automobileengine antifreezer can be practically effective for application to contact wires at railcar depots. In the present study, the railway contact wires are coated with anti-icing mixtures of ethylene glycol/tap water and glycerol/tap water at various ratios (v/v %) as well as with tap water alone, at temperatures of -30 and -40 °C in a deep freezer. The morphological change on the wire surfaces is observed under optical microscopy. The surface-contact angles are measured to examine the surface difference between uncoated and coated railway contact-wire fragments. Conclusively, the fragments coated with 40/60 and 60/40 (v/v %) ratios of ethylene glycol or glycerol with tap water, as compared with the uncoated fragments, are shown to have been effectively de-iced. The surface-characterizations data thus indicate that mixtures of glycerol or ethylene glycol with tap water can be practical de-icing agents for application to railway contact wires.

In this study, we designed and synthesized three blue fluorescence materials based on diarylamine-substituted pyrene derivatives. Organic Light Emitting-Diodes devices using these materials were fabricated in the following sequence; ITO/2-TNATA (300 Å)/NPB (200 Å)/ α , β -ADN: 10 wt% blue materials 1-3 (300 Å)/DNAB (300 Å)/Liq (20 Å)/Al (1000 Å). All devices showed highly efficient blue emissions. Particularly, a device using materials (3) shown highly efficient blue emission with luminous efficiency of 8.94 cd/A, power efficiency of 4.40 lm/W, external quantum efficiency of 6.62% at 20 mA/cm², respectively, and the CIE coordinates of (0.16, 0.23) at 6.0 V.

Two blue fluorescent materials based on diphenylaminoarylvinyl-substituted diphenylanthracene have been synthesized. Multilayered organic light-emitting diodes (OLED) with the following sequence; ITO/NPB (50 nm)/Blue materials (30 nm)/Bphen (30 nm)/Liq (2 nm)/Al (100 nm) were fabricated using these materials as emitters. Two devices exhibited blue electroluminescence. Particularly, a device using 6-(4-(10-phenylanthracen-9-yl)styryl)- N , N -diphenylnaphthalen-2-amine (2) exhibited blue emission with a luminance efficiency, a power efficiency, an external quantum efficiency and CIE coordinates of 5.69 cd/A, 1.99 lm/W, 3.39% at 100 mA/cm² and ( x = 0.19, y =0.31) at 8.0 V, respectively.

In this study, two anthracene derivatives with quinoline moieties were synthesized. To investigate their electroluminescent (EL) properties, multilayered OLEDs with the following sequence; indiumtin-oxide (ITO)/N, N'-di(1-naphthyl)-N, N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB) (20 nm)/Blue emitting materials (30 nm)/bathophenanthroline (Bphen) (30 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm) were fabricated using these materials as emitters. Two devices exhibited EL in blue to sky-blue regions. Especially, a device using 2,3-diphenyl-6-(10-(naphthalen-7-yl)anthracen-9-yl)quinoline (1) as an emitting material exhibited blue emission with a luminous efficiency, a power efficiency, an external quantum efficiency, and Commission International de L'Eclairage (CIE) coordinates of 1.01 cd/A, 0.43 lm/W, 0.80% at 20 mA/cm2, and (0.17, 0.22) at 6.0 V, respectively.

In this study, we designed and synthesized emitting materials based on naphthoanthracene derivatives. Organic Light Emitting-Diodes (OLEDs) devices using each four materials were fabricated. All devices showed efficient emissions. In particular, a device using 1-(5,5-Dimethyl-9-phenyl-[5H-naphth[3,2,1-de]anthracen-3-yl])-1H-indole as an emitter at 20 mA/cm2 exhibited luminous efficiency, power efficiency, and external quantum efficiency of 6.51 cd/A, 4.19 lm/W, and 2.48%, respectively, with Commission Internationale d'Énclairage (CIE) coordinates of (0.19, 0.49) at 7.0 V.

To investigate the electroluminescent (EL) properties of fluorescent materials based on fluorene-substituted naphthalene, multilayered OLEDs with the following sequence; indium- tin-oxide (ITO)/N,N'-di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB) (50 nm)/Blue emitting materials (30 nm)/4,7-diphenyl-1,10-phenanthroline (Bphen) (30 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm) were fabricated using these materials as emitters. These devices exhibited blue emissions. Particularly, a device using 7-(1-(1-(2-(diphenylamino)-9,9-diethyl-9H-fluoren-7- yl)naphthalen-4-yl)naphthalen-4-yl)-9,9-diethyl-N,N-diphenyl-9H-fluoren-2-amine as a blue emitting material exhibited blue emission with a luminous efficiency, a power efficiency, an external quantum efficiency, and CIE coordinates of 2.79 cd/A, 1.19 lm/W, 2.30% at 1,000 cd/m2, and (0.14, 0.12) at 8.0 V, respectively. This study demonstrates that 2-(Diphenylamino)-9,9-diethylfluorenes endcapped naphthalene derivatives have the excellent properties for blue emitting materials for OLEDs.

Owing to their chemical and thermal stability and doping effects on providing electrons to the conduction band, doped ZnO nanowires have generated interest for use in electronic devices. Here we report hydrothermally grown Fe-doped ZnO nanowires and their gas-sensing properties. The synthesized nanowires have a high crystallinity and are 60 nm in diameter and 1.7 μm in length. Field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) are employed to understand the doping effects on the microstructures and gas sensing properties. When the Fe-doped ZnO nanowire arrays were evaluated for gas sensing, responses were recorded through changes in temperature and gas concentration. Gas sensors consisting of ZnO nanowires doped with 3-5 at.% Fe showed optimum formaldehyde (HCHO) sensing performance at each working temperature.

We have synthesized four pyrene-derived blue emitting materials using Suzuki cross coupling reactions. All OLED devices using these materials as emitting materials showed efficient blue electroluminescence (EL). Particularly, a device using 1,1'-(9,9-dimethyl-9H-fluorene-2,7-diyl)bis-pyrene (1) showed best EL properties with the luminous efficiency of 4.32 cd/A, the power efficiency of 3.98 lm/W and the external quantum efficiency of 2.48% at 500 cd/m2.

We investigated efficient hybrid white organic light emitting diodes (WOLEDs) apply to triplet harvesting (TH) concept based on three complementary colors by mixing containing blue fluorescent emitter with phosphorescent emitters. The TH is to transfer these triplet excitons from a fluorescence to a phosphorescence, where they can decay radiatively. We fabricated several hybrid WOLEDs, having various emitting layer structures with blue fluorescent emitter and red, green phosphorescent emitter. The WOLED exhibited maximum luminous efficiency of 9.02 cd/A, and a maximum external quantum efficiency of 4.17%. The WOLED showed a highly color-stable white emission with the Commission International de L'Éclairage chromaticity of (0.38, 0.36) at 1,000 cd/m2.

We have designed and synthesized three emitters based on anthracene derivatives (1-3) containing various heterocyclic compounds via the Suzuki cross coupling reaction. Among those, a material showed efficient blue electroluminescent properties with a luminous, a power, and an external quantum efficiencies of 1.99 cd/A, 0.70 lm/W, and 1.17% at 20 mA/cm2, respectively.

A solution combustion process for the synthesis of perovskite (CaTiO3) powders is described. Perovskite is one of the crystalline host matrics for the disposal of high-level radioactive wastes (HLW) because it immobilizes Sr and Lns elements by forming solid solutions. Solution combustion synthesis, which is a self-sustaining oxi-reduction reaction between nitrate and organic fuel, the exothermic reaction, and the heat evolved convert the precursors into their corresponding oxide products above 1100 degrees C in air. To investigate the effects of amino acid on the combustion reaction, various types of fuels were used; a glycine, amine and carboxylic ligand mixture. Sr, La and Gd-nitrate with equivalent amounts of up to 20% of CaTiO3 were mixed with Ca and Ti nitrate and amino acid. X-ray diffraction analysis, SEM and TEM were conducted to confirm the formed phases and morphologies. While powders with an uncontrolled shape are obtained through a general oxide-route process, Ca(Sr, Lns)TiO3 powders with micro-sized soft agglomerates consisting of nano-sized primary particles can be prepared using this method.

In this study, we have designed and synthesized blue emitters based on quinoline-substituted 10-(naphthalene-7-yl)anthracene. Particularly, a material exhibited highly efficient blue electroluminescence with CIE coordinates of (0.15, 0.18).

Synroc (Synthetic Rock) consists of four main titanate phases: peroveskite (CaTiO3), zirconolite (CaZrTi2O7), hollandite (BaAl2Ti6O16) and rutile (TiO2). Nano-polycrystalline synroc powders were made by a synthesis combustion process. The combustion process, an externally initiated reaction is self-sustained owing to the exothermic reaction. A significant volume of gas is evolved during the combustion reaction and leads to loosely agglomerated powders. This exothermic reaction provides necessary heat to further carry the reaction in forward direction to produce nanocrystalline powders as the final product. Glycine is used as a fuel, being oxidized by nitrate ions. It is inexpensive, has high energy efficiency, fast heating rates, short reaction times and high compositional homogeneity. In this study, combustion synthesis of nano-sized synroc-B powder is introduced. The fabrication of synroc-B powder result of observation XRD were prepared for polycrystalline (perovskite, zirconolite, hollandite, rutile) structures. The characterization of the synthesized powders is conducted by using XRD, SEM/EDS and TEM.

In this paper, we fabricated tri-metal layered thin film semitransparent electrodes consisting of a thin conductive metal layer, sandwiched between two nickel layers. An equal red phosphorescent organic light-emitting diode (PHOLED) structure was deposited on the anodes of indium tin oxide (ITO) and three types of tri-metal layers (Ni/Al/Ni, Ni/Cu/Ni, and Ni/Ag/Ni, thickness of 3/7/3 nm in common) on a glass substrate. The optical and electrical performances of the device using Ni/Ag/Ni were improved more than the performances of the other devices due to the micro-cavity effect in accordance with the various electrode characteristics. Moreover, we fabricated the same red PHOLED structures on a flexible substrate, as a consequence, showed competitive emission characteristics compared to the devices fabricated on a glass substrate. Therefore, this study could succeed to additional research on flexible display panel and light-emitting devices with ITO-free electrodes.

In this study, two blue emitters based on 9,10-diphenylanthracene and 5H-pyrido[3,2-b]indole were designed and synthesized for OLEDs. Among those, a device using 5-(9,10-diphenyl-2-(5H-pyrido[3,2-b]indol-5-yl)anthracen-6-yl)-5H-pyrido[3,2-b]indole (2) exhibited efficient blue emission with a luminous, power and external quantum efficiency of 5.99 cd/A, 2.70 lm/W and 3.94% at 20 mA/cm2, respectively. The CIE coordinates of this device were (x = 0.15, y = 0.21) at 6.0 V.

Recently, white organic light-emitting diodes (OLEDs) have aroused considerable attention because they have the potential of next-generation flexible displays and white illuminated applications. White OLED applications are particularly heading to the industry but they have still many problems both materials and manufacturing. Therefore, we proposed that the new iridium compounds of orange emitters could be demonstrated and also applied to flexible white OLEDs for verification of potential. First, we demonstrated the chemical properties of new orange iridium compounds. Secondly, conventional two kinds of white phosphorescent OLEDs were fabricated by following devices; indium-tin oxide coated glass substrate/4,4'-bis[N-(napthyl)-N-phenylamino]biphenyl/N,N'-dicarbazolyl-3,5-benzene doped with blue and new iridium compounds for orange emitting 8 wt%/1,3,5-tris[N-phenylbenzimidazole-2-yl]benzene/lithium quinolate/aluminum. In addition, we fabricated white OLEDs using these emitters to verify the potential on flexible substrate. Therefore, this work could be proposed that white light applications can be applied and could be extended to additional research on flexible applications.

Phosphorescent organic light-emitting diodes (PHOLEDs) have shown a heterojunction system that is a bulk heterojunctioned emitting layer (EML). In our work, we have demonstrated an improvement in efficiency with a partial mixed host system in an EML. A mixed host system, which is mixed with a host material and an electron transporting material, was used on the red PHOLEDs. In general, the recombination zone is located at the electron transporting layer (ETL) side in typical PHOLEDs due to excessive accumulation at the interface. However, this study proposed the removal of interfaces through the advantage of a mixed host system and a mixed layer between EML and ETL sides to increase the electron mobility of the experiments. Detailed optical and electrical analysis of these phenomena, were demonstrated.

Blue fluorescent emitters based on anthracene-aryl amine-anthracene derivatives were studied for efficient OLEDs. Compound 1 exhibited efficient EL propereties with luminous and power efficien- cies of 4.50 cd/A and 1.75 lm/W at 200 mA/cm2, respectively and CIE coordinates of (0.18, 0.26) at 7.0 V.

We designed and synthesized two pyrene derivatives: 1,6-di-1-naphthalenyl-pyrene (1) 1,6-Bis(10- phenyl-9-anthracenyl)-pyrene (2). Two OLED devices were fabricated in the following sequence: ITO (180 nm)/4,4'-bis(N-(1-naphthyl)-N-phenylamino)bipheny (NPB) (50 nm)/Blue materials 1 and 2 (40 nm)/Tris(8-hydroxyquinolinato)aluminium (Alq3) (15 nm)/lithium quinolate (Liq) (2.0 nm)/Al (100 nm). Two devices showed efficient blue emissions. Particularly, a device using 2 as emitting material showed blue EL properties with luminous efficiencies of 3.19 cd/A, power efficiencies of 1.54 lm/W, quantum efficiency of 2.42% at 500 cd/m2 and CIEx,y coordinates of (0.19, 0.16) at 7 V.

Self-assembled monolayers of thiols (RSH), which are key elements in nanoscience and nanotechnology, have been used to link a range of materials to planar gold surfaces or gold nanoparticles. In this study, the adhesive performance of mercapto silane systems to dental noble metal alloys was evaluated in vitro and compared with that of commercial dental primers. Dental gold-palladium-platinum (Au-Pd-Pt), gold-palladium-silver (Au-Pd-Ag), and palladium-silver (Pd-Ag) alloys were used as the bonding substrates after air-abrasion (sandblasting). One of the following primers was applied to each alloy: (1) no primer treatment (control), (2) three commer- cial primers: V-Primer, Metal Primer II, and M.L. Primer, and (3) two experimental silane primer systems: 2-step application with 3-mercaptopropyltrimethoxysilane (SPS) (1.0 wt%) and then 3-methacryloxypropyltrimethoxysilane (MPS) (1.0 wt%), and a silane blend consisting of SPS and MPS (both 1.0 wt%). Composite resin cylinders with a diameter of 2.38 mm were bonded to the surfaces and irradiated for 40 sec using a curing light. After storage in water at 37 °C for 24 h, all the bonded specimens were thermocycled 5000 times before the shear bond strength test. Regardless of the alloy type, the mercapto silane systems (both the 2-step and blend systems) consistently showed superior bonding performance than the commercial primers. Contact angle analysis of the primed surfaces indicated that higher resin bond strengths were produced on more hydrophilic alloy surfaces. These novel mercapto silane systems are a promising alternative for improving resin bonding to dental noble metal alloys.

We have designed emitters based on Anthracene-Aryl-Anthracene moieties end-capped with 1-naphthyl groups. In particular, a device showed blue EL properties with luminous and power efficiencies of 1.95 cd/A and 0.93 lm/W at 200 cd/m2 respectively, and CIE coordinates of (0.16, 0.10) at 7.0 V.

In this paper, we demonstrated thin film semitransparent anode electrode using Ni/Ag/Ni (3/6/3 nm) on green and red phosphorescent OLEDs, which have basically high efficiency and good optical characteristics. Moreover, we applied this semitransparent anode on flexible green and red phosphorescent OLEDs, which were then optimized for possible applications on flexible substrates. First, we studied optimization using various conditions of Ni/Ag/Ni electrodes via transmittance and sheet resistance. We then fabricated the devices on a glass substrate with ITO or Ni/Ag/Ni electrodes as well as on a flexible substrate with a Ni/Ag/Ni electrode for green and red phosphorescent OLEDs. Consequently, we could be proposed that the potential of our semitransparent anode electrode is demonstrated. Green phosphorescent OLEDs characteristics using ITO or Ni/Ag/Ni anode electrodes were coincided and those of the red phosphorescent OLEDs were improved by semitransparent electrodes at 10,000 cd/m2 criterion. Therefore, this research suggests for additional studies to be conducted on flexible and high-performance phosphorescent OLED displays and light applications for ITO-free processes.

We have designed and synthesized three blue emitters based on 9-naphthylanthracene derivatives connected with various electron-withdrawing group such as 4-fluorobenzene, 2,4-difluorobenzene and 2,3,4,5,6-pentafluorobenzene (1-3). Multilayered OLEDs with the structure of ITO (180 nm)/NPB (50 nm)/Blue materials 1-3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/AI (100 nm) have been fabricated to investigate their electroluminescent properties. In particular, the device using 3 showed efficient blue electroluminescent properties with a luminous, power, external quantum efficiency and CIE coordinates of 0.71 cd/A, 1.98 Im/W, 1.34% at 20 mA/cm2 and (x = 0.16, y = 0.20) at 10.0 V, respectively. In addition, a deep blue OLED using 1 with CIE coordinates (x = 0.15, y = 0.11) at 10.0 V exhibited a luminous, power, external quantum efficiency of 2.12 cd/A, 3.04 Im/W and 1.17% at 20 mA/cm2, respectively.

We investigated a light emission mechanism of blue phosphorescent organic light emitting diodes (PHOLEDs), using a stepwise doping profile of 2, 8, and 14 wt.% within the emitting layer (EML). We fabricated several blue PHOLEDs with phosphorescent blue emitter iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,C2]picolinate doped in N,N'-dicarbazolyl-3,5-benzene as a p-type host material. A blue PHOLED with the highest doping concentration as part of the EML close to an electron transporting layer showed a maximum luminous efficiency of 20.74 cd/A, and a maximum external quantum efficiency of 10.52%. This can be explained by effective electron injection through a highly doped EML side. Additionally, a white OLED based on the doping profile was fabricated with two thin red EMLs within a blue EML maintaining a thickness of 30 nm for the entire EML. Keywords: Blue Phosphorescent Organic Light Emitting Diodes, Stepwise Doping Structure, Charge Trapping Effect.

We demonstrate that chitosan prepatterns can generate not only highly periodic DNA pattern but also various types of graphitic carbon materials such as single-walled carbon nanotubes (SWNTs), graphene oxide (GO) and reduced graphene oxide (RGO). Scanning electron microscopy (SEM), fluorescence imaging and Raman spectroscopic results revealed that the graphitic carbon materials were selectively deposited on the surface of the periodic chitosan patterns by the electrostatic interaction between protonated amine groups of chitosan and the negative charged carbon materials. One proof-of-concept application of the system to the fabrication of electrical devices based on the micropatterns of SWNTs and RGO was also demonstrated. The strategy to use highly surface active chitosan pattern that can easily fabricate highly periodic pattern via a variety of lithographic tools may pave the way for the production of periodic arrays of graphitic carbon materials for large area device integration.

Swine dysentery is a contagious mucohaemorrhagic colitis of pigs that is caused by anaerobic intestinal spirochaete Brachyspira hyodysenteriae. Recently, an outer membrane lipoprotein of B. hyodysenteriae (BmpB) has been identified, and the mice or pigs immunized with a recombinant BmpB generated antibodies recognizing the native BmpB of B. hyodysenteriae. In this study, we cloned, expressed and purified BmpB protein from E. coli and used it as a vaccine candidate for oral delivery. The BmpB was encapsulated into the pH-sensitive and thiolated Eudragit microspheres (TEMS). The sizes of the microspheres ranged from 5-20 μ. About 22-34% of BmpB were released from the BmpB-loaded TEMS within 24 h at stomach pH 2.0 whereas the release of BmpB from the BmpB-loaded TEMS was 35% in the first one hour and reached 81% within 24 h at intestinal pH 7.2. These data revealed that the BmpB could be protected in the harsh gastric condition. Mucoadhesive experiment in vitro showed that TEMS have high binding affinity with the mucin glycoproteins of porcine intestine. Finally, in vitro production of cytokines from immune cells treated with the BmpB-loaded TEMS suggested that the TEMS would be a promising approach for oral delivery of BmpB as vaccine candidate.

Receptor-mediated endocytosis is a promising approach of gene delivery into the target cells via receptor-ligand interaction. Vimentins at the cell surface are recently known to bind N-acetylglucosamine (GlcNAc) residue, therefore, the cell surfaces of vimentin-expressing cells could be targeted by using the GlcNAc residue as a specific ligand for receptor-mediated gene delivery. Here, we have developed polymeric gene delivery vectors, based on poly(ethylene oxide)(PEO) and poly(aspartamide), namely poly[(aspartamide)(diethylenetriamine)]-b-[PEO-(GlcNAc)] (PADPG) and poly[(aspartamide)(diethylenetriamine)]-b-[PEO] (PADP) to elucidate the efficiency of GlcNAc ligand for gene delivery through receptor mediated endocytosis. To determine the efficiency of these polymeric vectors for specific gene delivery, the DNA condensation ability of PADPG and PADP and the subsequent formation of polymeric nanoparticles were confirmed by gel retardation assay and transmission electron microscopy respectively. Both PADPG and PADP had lower cytotoxicity than polyethylenimine 25 K (PEI 25 K). However, their transfection efficiency was comparatively lower than PEI 25 K due to hydrophilic property of PEO in the vectors. To observe the stability of polymeric nanoparticles, the transfection of PADPG and PADP was carried out in the presence of serum. Favorably, the interfering effect of serum on the transfection efficiency of PADPG and PADP was also very low. Finally, when the cell specificity of these polymeric vectors was investigated, PADPG had high gene transfection in vimentin-expressing cells than vimentin-deficiency cells. The high transfection efficiency of PADPG was attributed to the GlcNAc in the polymeric vector which interact specifically with vimentin in the cells for the receptor-mediated endocytosis. The competitive inhibition assay further proved the receptor-mediated endocytosis of PADPG. Thus, this study demonstrates that conjugation of GlcNAc is an effective and rational way to prepare a suitable vector for targeted gene delivery to vimentin-expressing cells.

Green phosphorescent organic light emitting diodes (PHOLEDs) were developed using a mixed layer system. They were fabricated with 4,4'-N,N'-dicarbazolyl-biphenyl (CBP) and typical charge transporting materials, which are 4,4'-bis[N-(naphthyl)-N-phenylamino]biphenyl (NPB) as a hole transporting material and 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi) as an electron transporting material, mixed at each interface in a stacked organic layer to reduce the hole injection barrier and extend the recombination zone. We introduced a mixed layer for the hole transporting layer side, the electron transporting layer side, and on both sides to make a bulk heterojunction. This reduced the driving voltage, and the luminous efficiency (LE) was increased to 500 cd/m2. The optimized device showed a maximum LE of 59.87 cd/A and a maximum external quantum efficiency of 17.52%.

We suggested that Ni/Ag/Ni semitransparent electrodes for the exchange of indium-tin-oxide (ITO) electrode, which is the most commonly used as a transparent electrode in spite of the structural defects, limited supply of indium, and toxic, could be apply on flexible Organic Light-Emitting Diodes (OLEDs). Red phosphorescent OLEDs (PHOLEDs) using different types of electrodes as ITO and various conditions of Ni/Ag/Ni electrode were fabricated and analyzed. The electrical and optical properties of device using Ni/Ag/Ni electrode were improved than that of devices on ITO glass substrate at the 10,000 cd/m2 criterion due to the micro-cavity effect even though their transmittance has lower than ITO glass. In addition, we also fabricated red PHOLEDs of same structure on Ni/Ag/Ni flexible substrate of various conditions. As a result, flexible red PHOLED showed competitive characteristics compared to the device on a glass substrate. Therefore, this study could be suggested to additional research on flexible OLEDs display and light applications for ITO-free fabrication.

The authors describe the fabrication of white organic light-emitting diodes (WOLEDs) with dual electron transporting layers (D-ETL) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanhroline/ 4,7-diphenyl-1,10-phenanthroline (BPhen) and bis-(2-methyl-8-quinolinolate)-4-(phenylphenolato) aluminum/BPhen. Stepwise D-ETL easily transports electrons easily to the emitting layer and reduces the leakage of electrons. Therefore, WOLEDs with D-ETL show higher external quantum efficiency (EQE) when compared to a control WOLED with a single ETL device. The optimized WOLEDs showed a peak EQE of 13.0%, luminous efficiency of 27.4 cd/A, and Commission Internationale de L'Eclairage coordinates of (0.40, 0.39) at 1000 cd/m2.